The first one is correct because There're is shorter for There are and "There are a good answer to that question" doesn't sound correct right? Whereas the first one There's is short for There is so "There is a good answer to that question" Now that sounds grammatically correct right?
Just answered this question above
^^
Answer:Triple Alliance of Germany, Austria-Hungary and Italy, and the Triple Entente of France, Russia and Britain.
Explanation:
I would guess C i am not really sure but hope it helps
